Automatic light control



April 25, 1933. K. SCHNEWKER AUTOMATI C LIGHT CONTROL Filed Sept. 24, 1951 4 Sheets-Sheet l INVENTOR ALLr ,Q/zmccim" BY j J ATTORNEY April 25, 1933- K SCHNEIDER 1,905,511

' AUTOMATIC LIGHT CONTROL Filed Sept. 24, 1931 4 Sheets-Sheet 2 C) O O C) M r INVENTOR lei/mt c/flfldiev 5/ ATTORNEY April 25, 1933- K. SCHNEIDER AUTOMATIC LIGHT CONTROL Filed Sept. 24, 1931 4 Sheets-Shet 5 r I L INVENTOR ATTORNEY April 25, 1933. I K SCHNEIDER 1,905,511

AUTOMATIC LIGHT CONTROL Filed Sept. 24, 1931 4 Sheets-Sheet 4 I INVENTOR Kart j /gneidew ATTORNEY provided to cut all exposure values out of v Patented Apr. 25, 1933 UNITED sT-A KURT SCHNEIDER, OF BROOKLYIIN'EW YORK, ASSIGNOB '10 OEHL EB mom! commmn me, a coaronurron auromarrc near common Application filed September 24, 1981. 7 Serial No. 564,791.

This invention relates to improvements in automatic light controls,-and particularly to the automatic control of exposed lamps, such as are used in motion picture film printing machines. y

One of the principal objects of the invention is to provide means to properly ex ose each scene of a motion picture positive 'lm. This is accomplished in the followingsimple and efiicient manner: The device is set y means of a keyboard so that a correct intensity of light is registered for each scene. After the device is set it may bechecked by comparing the registered light intensities with those given by the printing, card, a record made when the negative was timed. After being set the device is ready to operate in conjunction with the breaker box of the printing machine. During the operation of the printing machine, the intensity of the printing light is automatically controlled by the device, so that any number of prints may be obtained from a given negative with the same sequence of light changes. A simple method is providedto enable the changing of the exposure intensity' for any one or more scenes, if it is deslrable to do so. A clearing means 1s also register, thus enabling the machine to be reset.

Another object of the invention is to pro vide means to control a number of electrical circuits so that they will operate individually in a predetermined order. Other applications of the invention are the setting and control of advertising signs, novelty displays, and other electrical apparatus employing a multiple contact system. A

An automatic light control, which embodies the principles of the invention, is shown in the accompanying drawings. y

In appearance the machine somewhat resembles a typewriter being about the same size and having a similar keyboard. It also has an indicating panel which registers a sequence of light changes for any number up to 160 scenes and shows'whether the machine is set for timing or for printing. Beneath the indicating panel is a small window through which may be viewed a drum dial which is read against a fixed scale. The

dial is graduated from 1 to 160 and the-scale is blocked out into three sections, in, set,

and .out. To the right of the window is mounted a shielded lamp which illuminates the keyboard consisting of 28 keys, 24 of which are numbered from 1 to 24, the other ,four being marked out, s

t, and Dial. A special feature of the w keyboard is that only one key can be operated at a time when settin the machine and when the switch on the rig 1: side of the machine is changed from the setting to the rinting position, all keys are automatically as ocked. In the drawings which accompany this disclosure:

Fig.1 shows a partial plan and sectional side view. 1o Fig. 21shows a partial plan and sectional front view.

Fig. 3 shows a top view, partly sectioned and with top removed.

Fig. 4 shows a detail view of the ratchet 15 operating mechanism.

Fig. 5 re resents a detail view of the clearing me'c anism.

Fig. 6 shows adetail view of the key locking mechanism.

Fig. 7 shows .a wiring diagram.

Before describing the construction of the machine it may be analyzed as consisting of the following'esse'ntial elements.

I.'-A drum driven by a ratchet movement 5 and adapted to carry balls.

II.A keyboard and lever mechanism. III.A contact mechanism. The drum 20, shown in Figures 1, 2, and 3, has milled upon its surface laterally no milled, concave grooves 20 which are transversely cut by twenty-four longitudinal grooves 112, thus being divided into twentyfour rows of lateral rooves 19. The drum is mounted on a sha t 106, runnin in the ball races 21 of the frame 94. T ere are also mounted on the shaft, a ratchet wheel 61, an elevating wheel 89, a drum dial 85, and a dial knob 107. The ratchet wheel has 160 teeth and is operated by the two ratchets 36 and 49. The drum dial is graduated from 1 to 160 and is illuminated by a pilot lamp. The dial is viewed through a window 82 and is read against a scale which is divided into three sections in, set, out. Interposed between the window and the dial is a lens 83, s rted in a mounting 84. The elevating wheel supports an internal gear, which turns around a stationar disc 91, having a guide roove and whic isadapted to receive bal s from the chute 117 and elevate them to the chute 92. The drum rotates in the cylindrical frame 94, having longitudinal guide rooves in its inner face (see Figure 2). V e cylinder is supported by the frame 11 and has in its lower end twenty-four slots arranged so that if a ball enters any one of the longitudinal grooves of the drum it must pass by way .of one of the slots and the chute 117 to the elevating wheel from which it is brou ht by way of the chute 92 and the ball magazine 87 to the shuttle 88, from which it is guided into one of the twenty-four channels 18.

At the end of each channel (see Figure 1) there is an openin 17, just large enough to hold two of the ba ls, which when the plunger 15 is not operated are prevented from entering a carrier groove by a sprin When a plunger 15 is operated, a sing e ba 1 is pushed into a carrier groove in that row which corresponds to the respective plunger which is operated. Beneath the plunger is a sleeve containing another plunger 63 and a ball 62, which is prevented from leaving the sleeve because the diameter of the sleeve is somewhat restricted at the ball end. As one of the smaller balls in a carrier roove passes a steel ball 62 in one of the s eeves, the ball 62 is forced into the sleeve and the contact plunger 63 is operated. Slides 97 and 98, a detail of which is shown in Fi re 5, are beneath each contact plun er an act to remove either one or all bal from the carrier grooves to the longitudinal or clearmg grooves.

Referring to Figures 1 and 2, it is seen that the keyboard has twenty-eight keys which operate various mechanisms b lever systems. All the keys are similar 1n that they all operate a lever 5 which is pivoted at bearing 10 and when released a spring 4 in sleeve 3 forces the key hack to its original position. Figure 1 shows a composite view of all the key lever mechanisms.

Thereare twenty-four numbered keys 101 the other four being marked All out, Step, One out and Dial. In order not to be able to operate more. than one key at a time, a locking device 26 (shown in detail in Figure 6) is employed. The locking device consists of a block bored and slottet. as in the drawing to allow a number of balls 27, to be kept in line by a plunger, spring and screw arrangement, 135-134-423 (Fig. 6) and 1permitting the o eration of one of the key evers 5 only, or t 1e lever 24, operated b the switch 22.

W en one of the numbered keys 101 is operated, one of the balls is pushed from one of the openings 17 into one of the carrier grooves of that row of grooves which corresponds to the key operated. This action is effected through the lever system 512- 1314-15 (Fig. 1). A pin 14 fastened to the lever 13 fits into a slot of the plunger 15 and a spring 16 acts to return the plunger when the key is released. Another action which accompanies the operation of a num bered ke is the reciprocating motion given to the s uttle, by means of the following levzr z)system, 5--57-'60111-114 (Figs. 1 an 2 A third action accompanying the operation of a numbered ke is the rotation of the drum one tooth. The is accomplished by means of the following mechanism: The system of levers 557-55122 (see detail view Figure 4) gives a reciprocating motion to the piston 133 which is slotted to receive levers 122 and 31 and which is rovided with a stop 129 and a shock absor r 130. The piston is connected to the core 30 of a magnet 28 supported by a block 29. The piston can be operated either magnetically or by presing one of the numbered keys or the step key. The lever 31 actuates lever 34, one end of which is fitted with a roller 32 so asto reduce friction and the other end being shaped to form a bearing for the ratchet 36. A spring 38 is connected between the 0st 37 fitted to the ratchet and the post 39 tted to the lever 34. Slide 42 running in the tracks 98 and 99 is forced a ainst the lever 34 by the spring 43. A w eel 41 is mounted so as to rotate in one end of the slide 42. From this part of the description it is seen that the real motive power of the drum is the spring 43, while operation of the magnet, the step key, or one of the numbered keys acts to com ress the spring only and to bring the rate et 36 into the next tooth of the ratchet wheel.

Operating the step key'causes the drum to be turned one ratchet tooth, and moves the shuttle as abovejdescribed.

Operatin the dial key releases the ratchets 36 and 49 so that the drum can be rotated freely and o crates the shuttle in the same manner as t e step or a numbered key. The system of levers 5-6744- 110 actuate the sliding arm 46, both ends of which act as cams to release both ratchets.

Pressing the all out key releases the ratchet 36 and operates the shuttle and the all out slide 137 (shown in detail view, Figure 5). If the dial knob is then rotated all the balls in the carrier grooves of the drum are shifted from the guide grooves 115 of the cylinder to the clearing grooves 112 of the drum.

Operating the one out key moves the one out slide 97 so that the ball at the slide is transferred from the guide groove 115 to the clearing groove 112.

The plunger contact mechanism is supported on the cylinder by two insulated posts 77 and 78, and its sections 73 and 74 (Fig. 1) are held together by two sets of screws 75 and 76 and serve asthe bearings, fortwenty-four plungers 65 which are con-.,

nected by the insulated bushings 64 to the lungers 63. Two insulated sections 71 and 2 separate the pilot lamps and the resistance circuit contacts 69 and 70 of which thereare twenty-four each. There are also twenty-four plunger contacts 68, which slide on the plungers 65 and are forced toward the stop 113 by the springs 67. Twenty four springs 66 act on the plungers to force twenty-four balls 62 to the end of the sleeves in which the plungers are fitted.

A-plunger contact circuit is closed whenever one of the balls set in a carrier. groove passes a ball in the end of one of the sleeves ecause while it passes it pushes the ball into the sleeve, thus moving the plunger away from the drum and allowing the spring 67 to force a plunger contact 68 against a pilot lamp contact 69 and a resistance circuit contact 70, by which means, one of the pilot lamps 79 illuminates one of the numbers 81 of the indicating panel, and connection is made to one of the resistances in series 79.

Referring to Figure 7, which shows a wiring diagram, it is seen that the switch 22 controls the changeover from settin to printing or vice versa and the position 0 the switch 18 indicated by the pilot lamps 79, 79'. The switch is connected by means of a lever to the key-locking device so thatno keys can be operated while the switch is in the printing position. The magnet 28 which is connecte to the ratchet mechanism is included in the printing circuit. The magnet is operated by the breaker box 1 which is a circuit breaker which closes the circuit each time a notched film asses it. Each time the circuit is closed, t e magnet and ratchet mechanism operates to turn the ratchet wheel one tooth and one of the contact plungers is acted upon by one of the balls the voltage of the printer lamp is regulated, the other being a pilot lamp circuit by means of which the degree of printing exposure is indicated.

All the pilot lamps including the indicator, dial, setting, and printing pilot Iain S, 8, 8, 79,79, require six volts, which is d livered from the secondary of a transformer 9, as shown in the diagram. I

When the switch is changed from the printing to the setting position, the magnet and the printing pilot lam circuits are opened, the keys are unlocke and the setting pilot lamp circuit is closed.

In operation, the following instructions for operating the machines are to be followed in order to achieve the general purpose of the invention.

The keyboard automatic light Change is designed to provide a simple and efficient means of timing and controlling the printing exposure, so that during the printing of motion picture film, a correct exposure isfobtained for each scene of the negative. Any number up to'160 scenes can be timed, each scenetlmed for one of twenty-four exposure values. A novel check-up method is provided by means of which mistakes in setting the light change can be easily detected and corrected.

' To set the machine, the first step is to put the switch in the setting position. This unlocks all the keys and l ghts the setting pilot bulb of the indicating panel. Operating the key marked Dial permits the dial knob (shown on the left in the drawings) to be rotated freely. The dial knob is turned until figure 1 of the dial is directly behind the section of the fixed scale marked In afterwhieh the dial key is released.

The machine is now set to record a series of light intensities; in the same order as the exposures to be given the print. instance, if inspection of a negative has shown that the first scene re uired exposure 5, key 5 is presseddown. I2 the next scene requires exposure 21, key 21 is operated. For each consecutive scene a key is operated, thenumber of the key. representing the required degree of exposure.

Having timed all scenes, we'are ready to set the machine for printing. The dial key is pressed down while the dial is rotated until figure 1 of the dial is directly behind For the section of the fixed scale marked Set,

after which the dial key is released. The switch is put in the printing position which lights the printing ilot bulb of the inicating panel and locks all the keys. 'The machine will now in conjunction with the breaker box of the printing machine, regulate the voltage supp ied to the printing lamp so that the proper sequence of light changes is obtained. I I

To make additional prints, it is necessary to bring figure 1 of the dial to the "set position of the fixed scale before making each print. This is done as has already been described by putting the switch in the setting position, pressing the dial key while the dial is rotated until figure 1 of the dial is at the set position, releasing the dial key, and returning the switch to the printing position.

Any number of prints may be made from a negative with the same sequence of light changes. If, however, it is believed that a print can be improved by giving a different exposure to any one or more scenes, the exposure for any scene can be changed in the following manner:

The dial is set so that the dial number corresponding to the number of the scene,

whose exposure is to be changed, is opposite out, after which the one out key is pressed. Then set the dial so that the number is opposite in, after which press the numbered key representing the new exposure intensity.

If itis desired to check the light changes for each scene with those given by the printing card, the machine is set as for setting and the step key is made use of. Beginning with scene 1, which is in line with set when viewed through the dial window,.the number representin the degree of exposure for that scene is ashed on the indicating panel. Pressing the step key brings scene 2 in line and the number representing the exposure intensity for the second scene is flashed on the indicating panel. Again pressing the step key, brings scene 3 in line and is accompanied by the flash of a. number representing the degree of exposure for the third scene etc.

If it is desired to reset the machine, all the exposure values can be cut out of register by turning the dial one revolution, while pressing down the all out key. The machine can now be set again as previously described.

It will be understood that I have described and shown the preferred arrangement of my device as one example only of the many possible wa s to practically construct the same and t at I may make such changes in the construction of the minor details and general arrangement of my automatic light control device as come within the scope of the appended claims without departure from the spirit of my invention, and the principles involved.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In a key operated machine for automatically controlling the exposure lamps used in motion picture film printing machines, a means for automatically locking the keys,

said means comprising a block having an axial bore for the reception of a number of balls, and a plurality of slots for the passage of the key levers, and a switch lever, a plunger, spring and screw arrangement in said bore permittin the operation of one of the key levers on y, and the switch lever selectively.

2. In a key operated machine for automatically controlling the exposure lamps used in motion picture film printing machines, a grooved drum adapted to receive balls, a cylinder in which said drum rotates, having longitudinal guide grooves in its inner face, a frame supporting said cylinder, said cylinder having twenty-four slots in its lower end, a chute upon which the balls from said drum are deposited through said slots, an elevating wheel for said balls, and a ball magazine into which said balls from said elevating wheel are deposited.

3. In a key operated machine for automatically controlling the exposure lamps used in motion picture film printing machines, a cylinder, a sectional plunger contact mechanism supported by insulated posts on said cylinder, two sets of screws holding the sections of said mechanism together, key operated plungers in said mechanism, sleeves for said plungers, and springs forcing a ball to the end of said sleeves and contacts for closing circuits by the operation of said plungers to illuminate pilot lamps.

4. In a key operated machine for automatically controlling the exposure lamps used in motion picture film printing machines, an indicating panel, for registering a sequence of light changes, timing and printing means, means on said indicating panel showing whether the machine is set for timing or for printing, a drum dial, a window for the inspection of said dial, and a fixed scale against which said dial is readable, said scale blocked out into three suitably marked sections.

. 5. In a key operated machine for auto matically controlling the exposure lamps used in motion picture film printing machines, a drum adapted to receive circuit closing balls,a shaft for said drum, a ratchet wheel on said shaft, and means for imparting to said drum a step by step motion said means comprising a system of levers, a slotted piston receiving a reciprocating motion from said system of levers, levers recessed in the slot of said piston, a stop for said piston, and a shock absorber, a magnet to the core of which said piston is connected, and a spring controlled slide controlling a ratchet in engagement with said ratchet wheel, said spring adapted to be compressed by a key to advance said drum for one step.

6. In a machine for automatically controlling the exposure lamps used in motion picture film printing machines, a rotating drum, with carrier grooves for the reception of balls, and means to close a number of pilot lamp circuits individually and in a predetermined order, said means being operated by the balls inserted in the carrierv key operated levers to select balls from a' supply and to insert the same into grooves in the surface of said drum, means to close a number of resistance circuits, indlvidually and in a predetermined order by the action.

of said balls against a number of plunger contacts and means to indicate which resistance circuit is closed, said means consisting.

of a number of pilot lamps, one of which corresponds to each resistance circuit.

8. In a key operated machine for automatically controlling the exposure lamps used in motion picture printing machines, a drum adapted to receive circuit closing balls, means of clearing any one ball without changing the circumferential position of the other balls for effecting the removal of the exposure value registered for any particular scene of a reel of motion picture negative film without the necessity of changing the sequence of the exposure values registered for the other scenes, said means including a scene dial and a fixed scale, said dial adapted to be rotated until the scene number corresponding to the number of the scene the exposure value of which it is desired to clear is opposite the legend Out on the fixed scale, and an out key the operation of which clears the exposure value registered for that particular scene.

9. In a key operatedmachine for automatically controlling the exposure lam s used in motion picture film prlnting mac ines, a drum adapted to receive circuit closing balls, means of re lacing a ball for one cleared ball for placing a new exposure value in re ister for one which has been cleared, said means comprising a scene dial and a fixed scale, said dial adapted to be rotated until the scene number corresponding to the number of the scene which has been cleared is opposite the legend Set on the fixed scale, and a key numbered to correspond to the new degree of exposure intensity for placing the new exposure value in register by its operation.

10. In a key operated machine for automatically controlling the exposure lamps used in motion picture film printing machines, an indicating panel for indicating whether the machine is set in a timing or printing position, said panel when set for timing indicating the intensity of light which each scene is timed for, and when set for the number of the scene for which a light printing indicating the degree of light intensity r each consecutive scene.

11.,In a key operated machine ,for automatically controlling the exposure lamps used in motion picture film printing machines, including a switch controlling the timing and printing operations of the machine, a key locking system permitting of ,the operation of one key at a time only and preventing the registering of more than one exposure value for each scene when the machine is being set, and locking automatically all keys upon the'setting of said switch controlling 'the timing or printing operations in theprinting position for preventing accidental manipulation of the keys during the printing operation.

12. In a key operated jmachine for auto- "matically controlling the exposure lamps used in motion picture film printing machines, including a pilot lamp, a scene dial, a fixed scale on one side of said dial marked In, Set and Out pointing to three different numbers on said scene dial, for exposing during the timing of the machine intensity value may be put in register, indicated by in), or the number of the scene for which a light intensity value may be taken out of register (indicated by out) and during the printing operation, the number of the scene which is beingprinted (indicated by set and the intensity of light with which that particular scene is being exposed (indicated at the time by the number on the indicating panel illuminated by said pilot lamp) and a step key for changing upon its depression during the setting of the machine the relation to the fixed scale, to the numbers on the scene dial, the depression of said step key rotating the scene dial for an equal step on each depression of the key, and a dial key rotatmg the scene dial upon its depression.

13. In a key operated machine for automatically controlling the exposure lamps used in motion picture film printing machines, a ball magazine and balls therein, and an internal gear and stationary disc mechanism for elevating and returning cleared balls into said magazine.

14. In a key operated machine for automatically controlling the exposure lamps used in motion picture film printing machines, including a fixed scale and a switch, a dial key, means for reproducing prints by pgessin'g the dial key permitting the dial to rotated until scene Number 1 is opposite a the mark set on the fixed scale, and means and a, magnetic circuit, a drum having circumferential grooves for retainin balls and longitudinal grooves for clearing balls, means to impart to said drum a. rotary mo- 5 tion in equal steps b the manual operation of said keys and t e interruption of the magnetic circuit, means for rotating said drum without changing any balls from their relative circumferential positions, a sta- 10 tionary cylinder having longitudinal guide grooves in its inner ce, a key operated slidin member for removin any one of the balls mm a guide groove 0 the cylinder to a clearing groove 0 the drum, and a key 0 erated sliding member for shunting all bafia from their circumferential positions on the drum into the clearing grooves of the drum and a chute for passing the balls from said clearin grooves to an elevating mechanism for their return to the ball magazine.

Signed at New York, in the county of New York, and State of New York, this 23rd day of September, A. D. 1931.

KURT SCHNEIDER. 

